So my daughter came home and said the low beams aren't working. We have been getting a stored P0563 (excessive volts) for about a week now showing up on the UG. I have the volts showing on the UG and they are within range, 13-14v. So I check the bulbs and both are burned out. I replaced them yesterday and the new ones burned out on me today. I also got pretty much every light on the dash come on. When that happened I looked at the UG and the volts were over 20v but quickly went back to 13-14v and the lights went off. It seemed to happen when I was coming to a stop and the engine RPM was slowing down.

So I am thinking voltage regulator. Any other ideas?

Thanks,
Jamie

 

I may have answered my own question. Pulled the alternator and took out the voltage regulator. The alternator spins very freely...like it will never stop when I spin it. It also squeals. I thought it was the pulley, but it's not. So I will replace the alternator.

 

My mechanic says often a bad battery can contribute to alternator failure. Also should check battery terminal connections and main ground connection for nice clean and shiny low resistance contact.

Thank you, by the way, for spelling out the OBD code definition. One of my peeves is when only the code number is posted. I guess sometimes posters don't want help that badly.

 

The P0563 is an excessive volts warning. It will trigger with more than 16v running through the truck.

I replaced the alternator because the old one was squealing. Now my volts are in the correct range ~14v and the P0563 has not triggered again. I probably could have gotten away with a $60 voltage regulator, but the alternator was less than $130 so I figured why not.

My last alternator was an eBay special that lasted well over 5 years. New one is from Rock Auto, but still a 'made in china' alternator. I'll be happy if I get 5 years out of this one.

Thanks,
Jamie